The present invention relates generally to apparatus that can detect and process printed indicia, such as that found on bar codes and matrix arrays, and more particularly to a self-contained, portable device that fully automates the steps used to acquire the indicia such that the device can be used in myriad environments where constant human interaction is impracticable, dangerous or both.
Bar code and related scanning devices are well known in the art. Such devices utilize a light-emitting transmitter to shine light on indicia either printed directly on a surface of a package, or affixed to a label, which in turn is adhered to the package. A portion of the light reflected from the printed indicia is captured by a receiving sensor, which converts the fluctuating reflections into a continuous analog signal. Electrical circuitry within the scanning device converts the analog signal to a digital equivalent, processes the information with reading circuitry according to predefined codes or algorithms, and compares the information against known criteria. When a match is achieved, a signal is sent to an output device, thereby producing human-intelligible information corresponding to salient features of the scanned item, such as description of the contents, price, weight, and the like. The more popular variants of bar code scanning devices are either autonomous portable, hand-held units, or large, stationary devices integrated with other machinery. The retail checkout environment has proven to be a popular end-use for both the portable and stationary variants of this technology, with U.S. Pat. Nos. 4,766,297 and 4,939,355 representative of the former and latter, respectively. Other commercial and industrial uses for such a system are also widespread; a recent example of such a system for the tracking of inventory or packages in transit is described in U.S. Pat. No. 6,094,642.
Advantages of known portable systems include compactness, flexibility of use, and relatively low acquisition and operating costs. The larger stationary systems, on the other hand, can more readily accommodate automation features that reduce the need for constant human intervention in the scanning process. Such automation can be an important attribute in situations involving harsh environments, where the environment itself could be deleterious to personnel health or safety. An additional benefit to including automation features is that opportunities for human-induced error are minimized, since excessive human participation introduces potential problems in data collection, sequencing, timing and accuracy. However, prior art stationary systems, while providing hands-free operation, tend to be heavy and complex, and thus not sufficiently mobile. In addition, many prior art automated systems are highly integrated with the host transport or conveyance machinery, such that power, trigger and control (such as a xe2x80x9chalt processxe2x80x9d command in the event an error is detected) is supplied via dedicated interconnects between the system and the machinery. This militates against system autonomy, and hence adaptability to myriad operating environments. Moreover, prolonged use of fully automated, unattended systems can lead to excessive wear of the equipment, even when the equipment is not in actual use. Additional problems can arise when such a system is deployed in environments that could induce misregistration and other similar erroneous data scans, such as where high vibratory loads are present. Common portable devices, on the other hand, such as hand-held lasers, wands and charge-coupled devices (CCDs), while inexpensive and flexible, generally require some degree of human attention, whether it is to activate the scanner (often by a trigger or similar switch), or to place the item to be scanned in a preferred alignment with the scanning device. While some automation features have been incorporated into handheld devices, providing triggerless scanning capability and direct transfer of data to storage, display or an external device, the prior art has not combined many of the valuable attributes of the portable and stationary systems into a self-contained package that provides the flexibility of portable systems with the functionality of larger, stationary units.
Accordingly, there is a need for an image-sensing device that can provide reliable reading of information found on data-containing labels and the like, with a self-contained device configuration that is readily adaptable to system mobility (i.e., transport, setup and operation) requirements.
This need is met by the present invention wherein a portable, stand-alone, self-contained system for reading printed indicia is disclosed. In the present context, xe2x80x9creadingxe2x80x9d an image encompasses a broad range of sensing functions, including the detection of an image by either active or passive means, whereas xe2x80x9cscanningxe2x80x9d an image is limited to the narrower subset whereby the reading is accomplished solely through an active device. With an active device, a receiver optically coupled to a dedicated coherent light-emitting transmitter detects reflections of light emanating from the transmitter, while a passive device detects random or incoherent background reflections or scattering from a diffuse light source, whether coupled to the detector or not. An example of the former is a laser with coupled photodetector, where the latter can be characterized by a conventional camera. According to one embodiment of the present invention, the system is a mobile automated data collection device that includes a rigid container (alternatively referred to as a housing or enclosure). The container itself is made of a base portion, which includes one or more internal compartments, a cover portion connected to the base and a handle. The device further includes a controller to send, receive and process electrical information, an extensible arm mounted at one end to the container or controller, and at the other end to a detector. The detector is comprised of an image-sensing apparatus (either a passive device, such as a camera, or an active device, such as a laser scanner), and circuitry to communicate images read by the image-sensing apparatus to the controller or related image-processing apparatus. The apparatus further includes a display in electrical communication with the controller such that, upon receipt of information from the detector, the controller instructs the display to show human-intelligible information corresponding to data contained in the detected image. The container""s one or more compartments can be adapted to receive and store the display, controller, extensible arm and detector when these components are not in use, while the handle allows a user to carry the device from one data collection location to another. By virtue of the stand-alone nature of the device, transport-induced vibrations (such as from a moving conveyor or production line) are not transmitted to the optically sensitive detector, thereby reducing the likelihood of vibration-related misreading. An additional benefit to being stand-alone is that it is easy to uncouple the system and move it to any transport machinery environment.
Optionally, the present embodiment includes pivotal mounting features for the extensible arm and the detector. Within the extensible arm is at least one tension spring and at least one locking joint. These features permit the arm to accommodate virtually any detector position needs. The wheels and the handle may be retracted to reduce the size of the container footprint, while the wheels may be locked to prevent unintentional movement during system operation. The construction of the container is such that when the cover and base (which can be hingedly attached) are closed, the container provides environmental shielding, offering protection against one or more forms of moisture or particulate contamination of the components disposed inside. The container""s one or more compartments can optionally house an information processing apparatus, which can then be electrically coupled to both the controller, as well as a second information processing apparatus, the latter through one or more data interchange ports mounted within the container.
According to another embodiment of the present invention, a container for a printed indicia reading device is disclosed. The container includes a rigid carryable enclosure that itself includes a base portion with at least one compartment disposed therein for storage of one or more components of the printed indicia reading device, a cover portion detachably connected to the base such that when the enclosure is closed, it provides environmental shielding of the internal components, and a handle to facilitate carrying of the device by a human user. The container further includes retractable wheels similar to that of the previous embodiment, as well as an articulating extensible arm mounted at a proximal end to the enclosure to permit multiple preferential positioning of the arm""s distal end. Optionally, the extensible arm includes the tension spring and locking joint arrangement of the previous embodiment, where the mounting arrangement produces a frictional, pivotal connection. Other options include the ability of the handle to retract into a recess in the enclosure, as well as environmental shielding similar to that discussed in conjunction with the previous embodiment. In addition, as with the previous embodiment, the wheels can include a locking feature to inhibit unintentional container motion. The container may further be outfitted with one or more data communication ports to facilitate the exchange of information between an optional information processing apparatus disposed within one of the compartments in the base and another information processing apparatus located outside the container.
According to another embodiment of the present invention, a method of using a mobile automated data collection device to read an object containing printed indicia is disclosed. The steps according to the method include: placing the device in operative proximity to a medium for transporting the printed indicia; deploying a detector, extensible arm, controller and output device, all of which can be contained within a storage container, such that the detector, controller and display are in electrical communication with one another, and further such that the detector mounts to the extensible arm, which in turn mounts to at least the container or controller to establish a mechanical communication therebetween. Additional steps include: transporting the object containing the printed indicia past the mobile automated data collection device so as to be in optical communication with it; sensing the presence of the object bearing the printed indicia; sending an input signal to the controller to indicate that the printed indicia is in optical communication with the mobile automated data collection device; having the detector read light reflected from the printed indicia; converting the reflected light to a digital representation of the information contained in the printed indicia; processing the digital representation in the controller so as to present data corresponding to the information contained in the printed indicia to an output device; and presenting the data corresponding to the information contained in the printed indicia in human-intelligible format with the output device.
Other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.